The invention relates to a press for compressing powdery material to grains comprising a loosely arranged, rotatable, annular, perforated mould supported and guided by a drivable mould holder and by an axially displaceable supporting member supporting the mould at the end remote from the mould holder, the side face of the mould adjoining the mould holder being urged by the supporting member with a given force against the mould holder in the operational position of the press in a manner such that during the operation of the press the mould is caught along by the mould holder owing to a force produced between the mould holder and the mould, whilst a rotatable roller is arranged in the mould.
Such a press is described in Dutch Patent Application No. 7701448. In itself this press operates satisfactorily, but it has been found that due to small shifts of the mould with respect to the mould holder during operation powdery material accumulates between the mould holder and the side face of the mould engaging the mould holder. This material may result in an undesirable displacement of the mould with respect to the mould holder.